Over the past five years, the European defense industry has undergone a dramatic restructuring. Economic forces and government policies have led to substantial industrial consolidation and the development of extensive transnational ties. Although there have been a number of efforts to promote transatlantic collaboration, most of the consolidation has taken place within and among European defense firms. Despite some efforts by national governments and such organizations as the Independent European Program Group and NATO to promote competition, there is a distinct trend toward national and transnational monopolies. Shrinking defense budgets have accentuated concerns about preserving defense industrial base, increasing the pressure for protectionism. Achieving the economic and political benefits of transatlantic collaboration and a competitive market will require more sustained U.S. and European government efforts to promote open access, eliminate trade barriers, and encourage industry-initiated transatlantic teaming.